Class: PennMARC::Language

Inherits:
Helper
  • Object
show all
Defined in:
lib/pennmarc/helpers/language.rb

Overview

Logic for extracting and translating Language values for a record. Penn practice is to verify the value present in the 008 control field as a three letter code. This code is then mapped to a display-friendly value using the a provided mapping hash.

Constant Summary collapse

UNDETERMINED_CODE =

Used when no value is present in the control field - still mapped

:und
LANGUAGE_SUBFIELDS = 
%w[a b d e g h i j k m n p q r t].freeze

Constants included from Util

Util::TRAILING_PUNCTUATIONS_PATTERNS

Class Method Summary collapse

Methods included from Util

#append_relator, #append_trailing, #datafield_and_linked_alternate, #field_defined?, #field_or_its_linked_alternate?, #join_and_squish, #join_subfields, #linked_alternate, #linked_alternate_not_6_or_8, #no_subfield_value_matches?, #prefixed_subject_and_alternate, #relator, #relator_join_separator, #relator_term_subfield, #remove_paren_value_from_subfield_i, #subfield_defined?, #subfield_in?, #subfield_not_in?, #subfield_undefined?, #subfield_value?, #subfield_value_in?, #subfield_value_not_in?, #subfield_values, #subfield_values_for, #substring_after, #substring_before, #translate_relator, #trim_punctuation, #trim_trailing, #trim_trailing!, #valid_subject_genre_source_code?

Class Method Details

.show(record) ⇒ Array<String>

Get language values for display from the 546 field and related 880.

Parameters:

  • record (MARC::Record)

Returns:

  • (Array<String>) —

    language values and notes



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# File 'lib/pennmarc/helpers/language.rb', line 17

def show(record)
  values = record.fields('546').map do |field|
    join_subfields field, &subfield_not_in?(%w[6 8])
  end
  language_values = values + linked_alternate(record, '546', &subfield_not_in?(%w[6 8]))
  language_values.uniq
end

.values(record, iso_639_2_mapping: Mappers.iso_639_2_language, iso_639_3_mapping: Mappers.iso_639_3_language) ⇒ Array<String>

Note:

In franklin, we extracted the language code from the 008 control field. After engaging cataloging unit representatives, we decided to also extract these values from the 041 field: Includes records for multilingual items, items that involve translation, and items where the medium of communication is a sign language. www.loc.gov/marc/bibliographic/bd041.html

Get language values for searching and faceting of a record. The values are extracted from subfields in the 041 field. Language facet and search values will typically be the same, with the exception of ‘zxx`, when no linguistic content is found.

Parameters:

  • record (MARC::Record)
  • iso_639_2_mapping (Hash) (defaults to: Mappers.iso_639_2_language) —

    iso-639-2 spec hash for language code translation

  • iso_639_3_mapping (Hash) (defaults to: Mappers.iso_639_3_language) —

    iso-639-3 spec hash for language code translation

Returns:

  • (Array<String>) —

    array of language values



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# File 'lib/pennmarc/helpers/language.rb', line 38

def values(record, iso_639_2_mapping: Mappers.iso_639_2_language, iso_639_3_mapping: Mappers.iso_639_3_language)
  values = record.fields('041').filter_map { |field|
    mapper = subfield_value?(field, '2', /iso639-3/) ? iso_639_3_mapping : iso_639_2_mapping
    field.filter_map do |sf|
      next unless LANGUAGE_SUBFIELDS.include? sf.code

      mapper[sf.value&.to_sym]
    end
  }.flatten
  control_field = record['008']&.value
  values << iso_639_2_mapping[control_field[35..37]&.to_sym] if control_field.present?
  values.empty? ? values << iso_639_2_mapping[UNDETERMINED_CODE] : values.uniq
end